Draftsman&#39;s apparatus.



G. s. SMITH. DRAFTSMANS APPARATUS.

APPLICATION FILED JULY 21, 190B.

Patented Aug. 13, 1912.

WLUIIBIA PLANGBAPH C0. WASHINGTON. D. Ci

25 1- my lnvention.

. so located that the sheet GLENN S. SMITH, OF WASHINGTON, DISTRICT OF COLUMBIA.

DRAFTSMAN S APPARATUS.

Specication of Letters Patent. Application filed July 21, 1908.

serial No. 444,664.

To all 'whom t may concern Be it known that I, GLENN S. SMITH, a5 citizen of the United States, residing at.` Washington, District of Columbia, have iny Vented new and usefulv Improvements in' Draftsmens Apparatus, of which the following is a specification.

This invention relates to apparatus adapted for use in map drawing, particu-` larly in the making of maps from heldv notes, such as are taken by surveyors.

While it may be used in the making of maps of any kind it has been found to be particularly adapted for platting railways, roads, canals, rivers, and the like, where the length of the finished map is great com-` pared with its width.

It has for its object to make it possible, as well as simple and easfy, to lay out or plat upon the sheet the nished map di-` rectly from the surveyors notes, and to acf complish this without the use of numerous instruments or complicated apparatus.

In the accompanying drawings: Figure 1 is a plan view of an apparatus embodying Fig.J 2 is a sectional view taken on the line IIII, of Fig. l.

edge and the arm by which it is Fig. 4 is a detached plan View of the carrier frame for the preti-actor. Fig. 5 is a plan View of a form of protractor particularly adapted for use in railway map drawing.

In the accompanying drawings 2 indicates a board or frame of suitable size having a plane upper surface, and, if found desirable, provided with supports or attachments by which it may be either carried by a stand or supported on a table. At its ends are mounted rollers 8 upon which is supported a strip or sheet of paper or fabric of transparent or semi-transparent material adapted to have the map made directly thereon, the rollers being supported' in suitable bearings in passing from close to the up- The shafts of milled heads them so that one roller to the other lies per surface of the board 2. the rollers are provided with l Or other means for turning i the sheet may be wound from one roller to the other.

5 indicates a rod suitably supported and preferably arranged close to and parallel with one of the rollers 3. Upon it is mount- 1 ed a carrier fora circular protractor 9. The

' spects being F ig. 3 is a detail perspective view illustrating the connection between the ruler or straight carried.

carrier comprises a sleeve the rod 5 and is free to slide thereon transversely of the board, an arm 8 and a thin plate (i carried by the arm and arranged t0 lie lla't upon the upper face of the board 2.

Patented Aug. 13, l

7 that encircles The plate has formed in its upper surface a shallow seat for the protractor 9, 0r is otherwise constructed to support it.' The size of the protractor is preferably as large as may be conveniently employed between the rollers 3, and when in use it is arranged lbetween the upper surface of the board and the sheet A, and is freely movable trans,- versely under the latter.

ln order to prevent'the protractor and its carrier from accidentally turning about the rod 5 and moving' away from the face of the board, with the result thatthe sheet might be torn, I may provide the board with a transverse under-cut slot 16, in which is adapted to travel a projecting lip 19 carried by the arm 8 of the carrier.

The protractor is peculiar in several reformed with a series of concentric circles constituting a linear measuring scale, and lines radiating from the said center, constituting the protractor proper. The circles are preferably numbered from the center outward, and are equally spaced apart according to the scale of the protractor so that by their use the distance of any point. from another point, no matter what its direction therefrom may be, can be easily determined by bringing the center of the protractor over the starting point and then counting the number of circles between the two points, whose distance apart it is desired to ascertain, along that radiating line which connects them. The radiating lines are marked to indicate degrees, the figures being preferably arranged in a circle near the periphery of the protractor. The base line marked 0 is usually also desi nated N, and in using Vthe apparatus is ta (en as the north line, whatever may be the positions to which the protractor may be adj usted. Around the peripheral edge of the protractor is a scale, l0, divided into degrees and properly marked, the numbering being preferably in the same direction as the numbering of the radiating lines, but with the zero mark arranged opposite the end of the 270o radiating line, that is to say, opposite the west line, though this particular arrangement merely chosen for convenience.

6 onk which it is supported, are rotatable about a center, which is the center from which the lines of the protractor radiate and about which the concentric circles are arranged. An arm, 20, of the laterally adjustable carrier frame extends beyond the edge of the protractor and is provided with an index, 11 which may be either a mark upon the arm 2O or a raised projection in the form of a pointer or index carried thereby. This arm preferably extends toward ythe left and the index mark, 11, thereon normally lies opposite the Zero mark ot the scale 10, in which position the north and south lines ot the protractor are parallel with the direction of movement of the sheet as it is wound from one roller to the other.

The protractor and its carrier, as stated, lie flat upon the surface of the board 2, with the sheet A passing over them, and, this being transparent, the lines of the protractor are easily seen through the sheet and may therefore be used to assist the drattsman in drawing the map which he may be producing. T suflicient care and skill be exercised maps or other plats or plans may be drawn with the assistance of this apparatus without the use of a ruler, straight edge, or curve, by following the proper lines of the protractor as they appear through the sheet. It greatly 'facilitates the use ot the apparatus however, to provide a straight edge or ruler that may be used in drawing all straight lines. Such ruler or straight edge is indicated at 12 and is hinged or pivoted to a carrying arm 13. This in turn is connected with the sleeve 7, so as to be movable back and forth across the board with the protractor, always maintaining a xed relation thereto. That portion of the carrying` arm situated between the part that lies parallel to the :tace ot the board 2 and the sleeve 7 is curved, as indicated at 17, to pass freely around the roller 3.

18 indicates a set-screw mounted in the sleeve 7 by means of which the protractor may be secured in theposition to which it may be adjusted. j

The pivot 14 uniting the straight edge or ruler with its carrying arm is located directly over the center of the protractor and in line with its axis ot rotation. The working edge of the ruler is so disposed that a line drawn by an instrument guided thereby will always radiate from the center of the protractor, no matter into what position it may be adjusted; and the inner end of its edge should preferably terminate at such center. It desired, the ruler may be formed at its inner end with a projection or oit-set, 15, adapted to form, in connection with the working edge, an angular seat for the point of a drawing instrument, located at the starting point for each line to be drawn, thatis, directly over the center of the protractor. The pivot 14 is mounted in brackets, 12, 13 carried respectively by the ruler or straight edge 12 and the arm 13 and constructed to stand sufficiently above the surface of the sheet A to allow the drawing instrument to follow the edge of the ruler quite to its inner or pivotal end.

For railway map drawing and some other kinds of work the protractor may be provided with a series of curves, in addition to the radiating lines and concentric circles, as indicated in Fig. 5. These curves spring from the center ot' the protractor, bending to the right and to the left respectively, and are of diiierent degrees of curvature, as curves of one degree, two degrees, three degrees, etc.

The method of 'using now be described.

Let it be supposed that it is desired to plat the field notes of the surveyors who have laid out a railway line. A strip of transparent paper or linen of a length tor the map, representing, let us say, titty miles of railway, is placed upon the rollers 3. The general direction of the line is then ascertained, which, it will be supposed, is 130 east of north. The protractor is then rothe instrument may tat-ed so that the radiating line indicating forty three degrees east of north stands lengthwise of the strip, that is to say, it is turned until the 130 mark of the scale 10 comes opposite the index line, 11. Then beginning near one end of the sheet a point is designated for the starting point of the line, and this is brought directly over the center of the protractor, which is easily accomplished by adjusting the sheet A and the protractor. The parts may position by the use of the set-screw 18, although this will not always be necessary. The surveyors notes are then read indicating the direction of the line from the starting point, which, it will be assumed, is 20 degrees east of north. The straight edge is then moved over the radiating line indicating this direction, such line being marked 20, and a line is drawn on rection, and ot a length called for by the notes and determined by the scale formed by the concentric circles, and a point is indicated at the end of this line. This point is then'brought over the center of the protractor, separate adjustments of the sheet and protractor being required for this purpose. From this point the road bends to the right with a tive degree curve. As the curves are all related to a single line as a tangent, the north and south line of the protractor being' chosen 'for this purpose, it follows that the straight line last drawn upon the sheet A must be brought to lie parallel with the said north and south line, or, in other words, the protractor must be adjusted about its center so as to bring these two lines into superbe fixed in this the sheet in that diposed relations, which, under the conditions just supposed, is secured by turning the protractor until the mark 20 of the scale 10 comes opposite the index 11. A line is then drawn on the sheet, following the five degree curve there indicated, for the proper distance, which may be determined by the use of the scale formed of the concentric circles, and a point located where the curve terminates. This point is then brought opposite to the center of the protractor by proper adjustments of the latter and the sheet. The protractor is then rotated back to its former position, that of 43 on the scale 10, and a line is drawn corresponding with the surveyors notes, which, it will be supposed, read north 62 east one mile, and apoint located thereon indicating the termination of the line in this direction. And thus the making of the map proceeds, the sheet and the prot-ractor being shifted each time there is a change in the direction of the line, and the point last located brought opposite to the center of the protractor.

In making maps where curves are not considered or represented, but only the angles between points, the position of the protractor does not have to be changed after having been first adjusted with reference to the longest dimension of the map.

In using an apparatus or device such as described, the work of the draftsman is reduced to a minimum. Calculations and adjustments are almost entirely eliminated, it being only necessary that the ruler or straight edge, which may be entirely .free and disconnected from the board if desired, be laid over the line of the protractor correspending with the direction given in the notes from which the plat or map 1s bemg made and the line drawn. Special care as to the length of the line need not at first be taken, as the point indicating its termination can be located by the use of the linear measurement scale formed by the concentric circles after the line is drawn. It matters not to what position the protractor may be set with reference to the board and the sheet A, its use is always the same--the draftsman follows the lines of the protractor corresponding with the reading of the notes from which he is working.

l/Vhat I claim is:

1. The combination of a board, supports for the sheet on which a map is to be drawn arranged to guide the sheet across the surface of the board, a movable protractor arranged to lie between the board and the sheet, and means for directing the movements of the protractor and maintaining' it in fixed angular relations to the sheet, substantially as set forth.

2. The combination of a board, supports for the sheeton which a map is to be drawn arranged to direct the sheet across the face of the board, a movable protractor arranged to lie between the board and the sheet, and means for directing the protractor whereby its movements are caused to be transverse relatively to the sheet, the protractor being rotatable about its own center.

3. The combination of a board, rollers supported thereby adapted to receive and guide a sheet on which may be drawn a map, a carrier or frame movable transversely of the sheet and arranged between it and the board, a protractor mounted on the carrier and rotatable, and an index movable with the carrier and with reference to which the protractor is rotatable.

4. The combination of a board, supports for a sheet on which a map may be drawn arranged to cause the sheet to lie over the face of the board, a movable protraetor arranged between the board and theI sheet, means for directing the movements of the protractor, and a ruler arranged above the sheet and having its working edge arranged over the center of the protractor.

5. The combination of a board, rollers supported near its opposite edges arranged to receive a sheet on which the drawing may be made, a guide rod parallel with the rollers, a carrier or support mounted on the guide rod, and a protractor mounted on the carrier and arranged to lie between the board and the drawing, the protractor being rotatable, substantially as set forth.

6. An apparatus adapted to be used in drawing maps, comprising a base board, a movable protractor arranged to lie between the base board and the sheet on which the drawing is to be made, and a ruler movable with the protractor arranged to lie above the sheet on the side thereof opposite t-he protractor, substantially as set forth.

7. An apparatus adapted to be used in making maps, comprising a base board, a protractor arranged to lie between the base board and the drawing sheet, and a ruler arranged to lie on the side of the sheet opposite the protractor, the ruler being movable with the protractor, and being also angularly adjustable, its center of angular adjustments being located over the center of the protractor, substantially as set forth.

8. An apparatus adapted to be used in drawing maps, comprising a base board, supports for holding a sheet of paper on the board, a protractor arranged to lie between the board and the drawing sheet, a movable carrier for the protractor, an arm connected with the carrier and exetending above the sheet, a ruler pivotally connected with the said arm arranged to lie above the sheet, the connecting parts of the arm and the ruler being elevated relative to the ruler and the pivot being arranged above the center of the protractor.

9. In an apparatus adapted to be used in prevent-ing .the protractor Jfrom being aceimap drawing, the combination of a base dentally moved away from the face of the board, supports for the sheet on which the board.

map is to be drawn, a protractor arranged GLENN S. SMITH. 5 to lie between the board and the sheet, means Witnesses:

for directing the movements of the protrac- J. S. BAKKER,

tor transversely of the sheet, and means for GEO. B. Prr'rs.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

